Annoying as the jack broke just as we were loading to go to Scotland for a two week trip, tried to get appart but it's beaten me and I don't have time to do much with it this evening, so probably looking at a new one. Doh.

The inner leg isn't moving the motor turns etc and I can pull the leg in and out so something in the drive, threadded part has bust I think, just emailed happijack for advice and will call niche I the morning session if they have one to sell. Could pop in on our way back from Scotland maybe

Well happijack got back on e mail within an hour and said It appears that the acme nut is no longer working with the drive screw. Over time, they sometimes get small particles of corrosion or something that gets embedded with the grease, and it eventually grinds away the threads on the nut. That mechanism is sealed inside the leg and is not repairable. Your option is to replace with model 4160 (direct replacement), our part #308169.

Guess you can't manage with it so a new one and repair if possible your existing perhaps, TBH I can quite see the grease trapping debrison other jacks I'm not convinced using a torquey drill is a great idea given the cost

The nut on my jack failed . I got it apart with some difficulty . The nut is a "special" made from what looks like Nylon . I did enquire about having them remade in bronze , but it didn't really add up . The legs from USA are not a bad price but with shipping and VAT it is not much different from Niche .